Wiping products made according to a low temperature delamination process

ABSTRACT

The present invention is generally directed to paper products having great softness and strength. The paper products are formed from a paper web that can be made according to various methods. In one embodiment, the paper web is an uncreped through-air dried web. The web can contain softwood fibers in combination with high-yield fibers. For example, the high-yield fibers can be contained in the middle layer of a stratified fiber furnish. In accordance with the present invention, a first bonding material is applied to a first side of the web and a second bonding material is applied to a second side of the paper web. The bonding materials are applied according to preselected patterns. At least one side of the paper web is creped after one of the bonding materials is applied. The bonding material applied to the creped side of the web can be an adhesive selected that allows the web to be creped at relatively low temperatures.

BACKGROUND OF THE INVENTION

[0001] Absorbent paper products such as paper towels, facial tissues andother similar products are designed to include several importantproperties. For example, the products should have good bulk, a soft feeland should be highly absorbent. The product should also have goodstrength even while wet and should resist tearing. Unfortunately, it isvery difficult to produce a high strength paper product that is alsosoft and highly absorbent. Usually, when steps are taken to increase oneproperty of the product, other characteristics of the product areadversely affected. For instance, softness is typically increased bydecreasing or reducing fiber bonding within the paper product.Inhibiting or reducing fiber bonding, however, adversely affects thestrength of the paper web.

[0002] One particular process that has proved to be very successful inproducing paper towels and wipers is disclosed in U.S. Pat. No.3,879,257 to Gentile, et al., which is incorporated herein by referencein its entirety. In Gentile, et al., a process is disclosed in which abonding material is applied in a fine, spaced apart pattern to one sideof a fibrous web. The web is then adhered to a heated creping surfaceand creped from the surface. A bonding material is applied to theopposite side of the web and the web is similarly creped. The processdisclosed in Gentile, et al. produces wiper products having exceptionalbulk, outstanding softness and good absorbency. The surface regions ofthe web also provide excellent strength, abrasion resistance, andwipe-dry properties.

[0003] Although the process and products disclosed in Gentile, et al.have provided many advances in the art of making paper wiping products,further improvements in various aspects of paper wiping products remaindesired. For example, many commercially available adhesives that may beused in the process disclosed in Gentile, et al. require that the paperproduct be placed on a heated creping surface prior to being creped fromthe surface. Further, in order for the adhesives to be subjected to asufficient amount of heat, the paper must remain on a heated crepingsurface for an extended period of time requiring the creping drum tohave a relatively large diameter. Thus, many conventional print bondedcreping processes have high energy requirements.

[0004] In view of the above, a need exists for a print creping processthat requires less energy in producing a product. In particular, it isbelieved that the process can be made much more economical if anadhesive can be selected that has lower temperature requirements duringcreping. Further, a need also exists for a single creped product thathas improved properties and characteristics.

SUMMARY OF THE INVENTION

[0005] In general, the present invention is directed to a method forproducing paper products. The paper products can be, for instance, papertowels, industrial wipers, facial tissues, bath tissues, napkins, andthe like. The process includes the steps of providing a paper webcontaining papermaking fibers. A first bonding material is applied to afirst side of the web in a preselected pattern. A second bondingmaterial is applied in a preselected pattern to the second side of theweb. The second side of the web is then adhered to a creping surface ata temperature of greater than about 50° F. and less than about 200° F.More particularly, the temperature of the creping surface is less thanabout 150° F., and in one embodiment is at ambient temperatures. Onceadhered to the creping surface, the second side of the web is crepedfrom the creping surface using a creping blade.

[0006] Thus, in one embodiment, the present invention is generallydirected to a print creping process that can occur at relatively lowertemperatures. Further, since the creping adhesive used in the presentinvention does not require relatively large amounts of heat in order tobond to a creping surface, the paper product treated in accordance withthe present invention can remain on a creping surface for a period oftime much shorter in duration than many conventional processes. As such,the creping drum in the process of the present invention can have asmaller diameter than many drums used in the past in similar processes.

[0007] The papermaking fibers used to construct the paper web of thepresent invention can vary depending on the particular application. Forinstance, hardwood and softwood fibers can be used. In one embodiment,the paper web can also include high-yield fibers, such asthermomechanical pulp. The high-yield fibers can be present in the webin an amount from about 5% to about 40% by weight. In one embodiment,the paper web is a single ply web containing multiple layers. The webcan include a middle layer containing the high-yield fibers either aloneor in combination with other fibers such as softwood fibers and/orhardwood fibers. The outer layers can also contain softwood fibers.

[0008] The paper web that is treated in accordance with the presentinvention can be made according to different processes. For example, theweb can be a wet-creped base sheet or an uncreped through-air dried basesheet. The paper web can have a basis weight of from about 15 gsm toabout 110 gsm, and particularly from about 35 gsm to about 70 gsm.Besides different types of fibers, the web can also contain a debondingagent. For example, a debonding agent can be present in the web in anamount from about 1 kg per metric tonne to about 6 kg per metric tonnebased upon the total weight of fibers contained in the web.

[0009] As described above, a first bonding material is applied to thefirst side of the web in a preselected pattern, while a second bondingmaterial is applied to the second side of the web in a preselectedpattern. The first and second bonding materials can be the samematerials or can be different bonding materials. Further, the patternsthat are used to apply the bonding materials can be the same ordifferent. For example, the patterns can be reticulated patterns or canbe patterns that comprise a succession of discrete shapes.

[0010] In one embodiment, when only creping one side of the web, thesecond bonding material is added in a manner that covers a greateramount of surface area than the first bonding material. In general, thefirst and second bonding materials can be applied to the first andsecond sides of the paper web in a combined amount of from about 2% to25% by weight of the paper web, particularly about 4% to about 10% byweight, and more particularly from about 6% to about 8% by weight of theweb.

[0011] In one embodiment, the bonding materials can be applied to eachside of the paper web in patterns that comprise a succession of discreteshapes. For instance, the bonding material can be applied to the firstside of the paper web (uncreped side) in a pattern that comprises asuccession of discrete dots. The bonding material applied to the secondside of the web (creped side), on the other hand, can comprise asuccession of, for instance, hexagons. The patterns applied to the firstand second sides of the web can cover approximately the same amount ofsurface area. For instance, each pattern can cover from about 25% toabout 75% of the surface area on each side of the web, and particularlyfrom about 40% to about 60% of the surface area of each side of the web.

[0012] As described above, however, in one embodiment, the bondingmaterial applied to the second side or the creped side of the web cancover a greater amount of surface area than the bonding material appliedto the first side of the web. In this embodiment, for instance, thebonding material applied to the second side of the web can cover greaterthan about 45% of the surface area of the second side of the web, andparticularly can be applied in a pattern that covers greater than about50% of the surface area of the second side of the web. The bondingmaterial applied to the first side of the web, however, can be appliedin a manner that covers less than the surface area covered by thebonding material applied to the second side of the web. For example, thebonding material applied to the first side of the web can be applied ina manner that covers less than 50% of the surface area of the web.

[0013] In accordance with the present invention, the second bondingmaterial that is applied to the web is a bonding material that willadhere to a creping surface at relatively low temperatures, such as lessthan about 150° F. The bonding material can have a glass transitiontemperature of from about 10° C. to about −20° C.

[0014] The through-air dried web can also undergo rush transfer betweentwo web conveying devices in the papermaking line, such as between afirst fabric and a second moving fabric prior to applying the bondingmaterials. The second fabric can be downstream from the first fabric andcan move at a speed that is about 5% to about 45% slower than the firstfabric.

[0015] Through the process of the present invention, various paperproducts can be formed. The paper products can be single-ply productsthat can be used in various wiping applications.

[0016] Other features and aspects of the present invention are discussedin greater detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] A full and enabling disclosure of the present invention,including the best mode thereof to one of ordinary skill in the art, isset forth more particularly in the remainder of the specification,including reference to the accompanying figures in which:

[0018]FIG. 1 is a schematic diagram of a paper web forming machine,illustrating the formation of a stratified paper web having multiplelayers in accordance with the present invention;

[0019]FIG. 2 is a schematic diagram of one embodiment of a process forforming uncreped through-dried paper webs for use in the presentinvention;

[0020]FIG. 3 is a schematic diagram of one embodiment of a process forforming wet creped paper webs for use in the present invention;

[0021]FIG. 4 is a schematic diagram of one embodiment of a process forapplying bonding materials to each side of a paper web and creping oneside of the web in accordance with the present invention;

[0022]FIG. 5 is a plan view of one embodiment of a pattern that is usedto apply bonding materials to paper webs made in accordance with thepresent invention;

[0023]FIG. 6 is another embodiment of a pattern that is used to applybonding materials to paper webs in accordance with the presentinvention; and

[0024]FIG. 7 is a plan view of another alternative embodiment of apattern that is used to apply bonding materials to paper webs inaccordance with the present invention.

[0025] Repeat use of reference characters in the present specificationand drawings is intended to represent same or analogous features orelements of the present invention.

DETAILED DESCRIPTION

[0026] It is to be understood by one of ordinary skill in the art thatthe present discussion is a description of exemplary embodiments only,and is not intended as limiting the broader aspects of the presentinvention, which broader aspects are embodied in the exemplaryconstruction.

[0027] In general, the present invention is directed to a process forproducing paper wiping products having great softness and strengthcharacteristics. In particular, the wiping products have high strengthvalues when either dry or wet. Further, the products have good stretchcharacteristics and are tear resistant. The products also have anincreased sheet caliper, and increased bulk.

[0028] The process of the present invention generally involves applyinga first bonding material to a first side of a base sheet or paper web. Asecond bonding material, which can be the same or different from thefirst bonding material, is applied according to a preselected pattern tothe second side of the paper web. The second side of the paper web isthen adhered to a creping surface and creped from the surface.

[0029] In accordance with the present invention, the second bondingmaterial used in the present invention is a bonding material that willadhere to a creping surface at a relatively low temperature. Forinstance, during the creping process, the creping surface can be heatedto a temperature of less than about 200° F., particularly at atemperature of less than about 150° F. and more particularly at atemperature of less than about 125° F. In one embodiment, for instance,the creping surface can be at ambient temperatures.

[0030] Many advantages and benefits can be realized when using a crepingadhesive that has relatively low temperature requirements. For instance,the total energy requirements of the process are significantly reduced.Further, when using a low temperature creping adhesive, the web need notremain on the creping surface for any extended period of time. As such,the size of the creping drum can be reduced and/or the web can remain onthe creping drum for a relatively short period of time. For example, theweb can remain on the creping drum for a period of less than about 0.3seconds, particularly for a period of less than about 0.25 seconds andmore particularly for a period of less than about 0.22 seconds. Byshortening the amount of time the paper is required to be on the crepingdrum, the process becomes faster and more efficient and capable ofproducing more product per unit time.

[0031] The second bonding material can have a glass transitiontemperature of less than about 10° C., particularly less than about −5°C., and more particularly can have a glass transition temperature offrom about 10° C. to about −20° C.

[0032] In accordance with the present invention, the bonding materialsare applied to the paper web in preselected patterns for providingstrength and stretchability. Creping the web, on the other hand, causesdelamination and increases the sheet caliper and cross-directionalstretch of the web. By increasing caliper, creping also increases thebulk of the sheet making the paper web feel softer.

[0033] Paper webs processed according to the present invention can bemade in different manners and can contain various different types offibers. In general, however, the paper web contains papermaking fibers,such as softwood fibers. In addition to softwood fibers, the paper webcan also contain hardwood fibers such as eucalyptus fibers and/orhigh-yield pulp fibers.

[0034] As used herein, “high-yield pulp fibers” are those papermakingfibers produced by pulping processes providing a yield of about 65percent or greater, more specifically about 75 percent or greater, andstill more specifically from about 75 to about 95 percent. Yield is theresulting amount of processed fiber expressed as a percentage of theinitial wood mass. Such pulping processes include bleachedchemithermomechanical pulp (BCTMP), chemithermomechanical pulp (CTMP)pressure/pressure thermomechanical pulp (PTMP), thermomechanical pulp(TMP), thermomechanical chemical pulp (TMCP), high-yield sulfite pulps,and high-yield kraft pulps, all of which leave the resulting fibers withhigh levels of lignin. High-yield fibers are well known for theirstiffness (in both dry and wet states) relative to typical chemicallypulped fibers. The cell wall of kraft and other non-high-yield fiberstends to be more flexible because lignin, the “mortar” or “glue” on andin part of the cell wall, has been largely removed. Lignin is alsononswelling in water and hydrophobic, and resists the softening effectof water on the fiber, maintaining the stiffness of the cell wall inwetted high-yield fibers relative to kraft fibers. The preferredhigh-yield pulp fibers can also be characterized by being comprised ofcomparatively whole, relatively undamaged fibers, high freeness (250Canadian Standard Freeness (CSF) or greater, more specifically 350 CFSor greater, and still more specifically 400 CFS or greater), and lowfines content (less than 25 percent, more specifically less than 20percent, still more specifically less that 15 percent, and still morespecifically less than 10 percent by the Britt jar test).

[0035] In one embodiment of the present invention, the paper webcontains softwood fibers in combination with high-yield pulp fibers,particularly BCTMP fibers. BCTMP fibers can be added to the web in orderto increase the bulk and caliper of the web, while also reducing thecost of the web.

[0036] The amount of high-yield pulp fibers present in the sheet canvary depending upon the particular application. For instance, thehigh-yield pulp fibers can be present in an amount of about 2 dry weightpercent or greater, particularly about 15 dry weight percent or greater,and more particularly from about 5 dry weight percent to about 40 dryweight percent, based upon the total weight of fibers present within theweb.

[0037] In one embodiment, the paper web can be formed from multiplelayers of a fiber furnish. The paper web can be produced, for instance,from a stratified headbox. Layered structures produced by any meansknown in the art are within the scope of the present invention,including those disclosed in U.S. Pat. No. 5,494,554 to Edwards, et al.,which is incorporated herein by reference.

[0038] In one embodiment, for instance, a layered or stratified web isformed that contains high-yield pulp fibers in the center. Becausehigh-yield pulp fibers are generally less soft than other papermakingfibers, in some applications, it is advantageous to incorporate theminto the middle of the paper web, such as by being placed in the centerof a 3-layered sheet. The outer layers of the sheet can then be madefrom softwood fibers and/or hardwood fibers.

[0039] For example, in one particular embodiment of the presentinvention, the paper web contains outer layers made from softwoodfibers. Each outer layer can comprise from about 15% to about 40% byweight of the web and particularly can comprise about 25% by weight ofthe web. The middle layer, however, can comprise from about 40% to about60% by weight of the web, and particularly about 50% by weight of theweb. The middle layer can contain a mixture of softwood fibers and BCTMPfibers. The BCTMP fibers can be present in the middle layer in an amountfrom about 40% to about 60% by weight of the middle layer, andparticularly in an amount of about 50% by weight of the middle layer.

[0040] The paper web of the present invention can also be formed withouta substantial amount of inner fiber-to-fiber bond strength. In thisregard, the fiber furnish used to form the base web can be treated witha chemical debonding agent. The debonding agent can be added to thefiber slurry during the pulping process or can be added directly intothe head box. Suitable debonding agents that may be used in the presentinvention include cationic debonding agents such as fatty dialkylquaternary amine salts, mono fatty alkyl tertiary amine salts, primaryamine salts, imidazoline quaternary salts, silicone quaternary salt andunsaturated fatty alkyl amine salts. Other suitable debonding agents aredisclosed in U.S. Pat. No. 5,529,665 to Kaun which is incorporatedherein by reference. In particular, Kaun discloses the use of cationicsilicone compositions as debonding agents.

[0041] In one embodiment, the debonding agent used in the process of thepresent invention is an organic quaternary ammonium chloride andparticularly a silicone based amine salt of a quaternary ammoniumchloride. For example, the debonding agent can be PROSOFT TQ1003marketed by the Hercules Corporation. The debonding agent can be addedto the fiber slurry in an amount of from about 1 kg per metric tonne toabout 6 kg per metric tonne of fibers present within the slurry.

[0042] In an alternative embodiment, the debonding agent can be animidazoline-based agent. The imidazoline-based debonding agent can beobtained, for instance, from the Witco Corp. The imidazoline-baseddebonding agent can be added in an amount of between 2.0 to about 15 kgper metric tonne.

[0043] In one embodiment, the debonding agent can be added to the fiberfurnish according to a process as disclosed in PCT Application having anInternational Publication No. WO 99/34057 filed on Dec. 17, 1998 or inPCT Published Application having an International Publication No. WO00/66835 filed on Apr. 28, 2000, which are both incorporated herein byreference. In the above publications, a process is disclosed in which achemical additive, such as a debonding agent, is adsorbed ontocellulosic papermaking fibers at high levels. The process includes thesteps of treating a fiber slurry with an excess of the chemicaladditive, allowing sufficient residence time for adsorption to occur,filtering the slurry to remove unadsorbed chemical additives, andredispursing the filtered pulp with fresh water prior to forming anonwoven web.

[0044] Referring to FIG. 1, one embodiment of a device for forming amulti-layered stratified pulp furnish is illustrated. As shown, athree-layered head box generally 10 includes an upper head box wall 12and a lower head box wall 14. Head box 10 further includes a firstdivider 16 and a second divider 18, which separate three fiber stocklayers.

[0045] Each of the fiber layers comprise a dilute aqueous suspension ofpapermaking fibers. In one embodiment, for instance, middle layer 20contains southern softwood kraft fibers either alone or in combinationwith other fibers such as high yield fibers. Outer layers 22 and 24, onthe other hand, contain softwood fibers, such as northern softwoodkraft.

[0046] An endless traveling forming fabric 26, suitably supported anddriven by rolls 28 and 30, receives the layered papermaking stockissuing from head box 10. Once retained on fabric 26, the layered fibersuspension passes water through the fabric as shown by the arrows 32.Water removal is achieved by combinations of gravity, centrifugal forceand vacuum suction depending on the forming configuration.

[0047] Forming multi-layered paper webs is also described and disclosedin U.S. Pat. No. 5,129,988 to Farringtonne, Jr., which is incorporatedherein by reference.

[0048] The basis weight of paper webs used in the process of the presentinvention can vary depending upon the final product. For example, theprocess of the present invention can be used to produce tissue webs,paper towels, industrial wipers, and the like. For these products, thebasis weight of the paper web can vary from about 15 gsm to about 110gsm, and particularly from about 35 gsm to about 70 gsm. In oneparticular embodiment, it has been discovered that the present inventionis particularly well-suited for the production of wiping products havinga basis weight of from about 53 gsm to about 63 gsm.

[0049] As stated above, the manner in which the paper web is formed canalso vary depending upon the particular application. In general, thepaper web can be formed by any of a variety of papermaking processesknown in the art. For example, the paper web can be a wet-creped web, acalendared web, an embossed web, a through-air dried web, a crepedthrough-air dried web, an uncreped through-air dried web, as wellvarious combinations of the above. In one particular embodiment of thepresent invention, however, the paper web is made in an uncrepedthrough-air dried process. It has been discovered that uncrepedthrough-air dried webs provide particular advantages when used in theprocess of the present invention.

[0050] For example, referring to FIG. 2, shown is a method for makingthroughdried paper sheets in accordance with this invention. (Forsimplicity, the various tensioning rolls schematically used to definethe several fabric runs are shown but not numbered. It will beappreciated that variations from the apparatus and method illustrated inFIG. 2 can be made without departing from the scope of the invention).Shown is a twin wire former having a papermaking headbox 34, such as alayered headbox, which injects or deposits a stream 36 of an aqueoussuspension of papermaking fibers onto the forming fabric 38 positionedon a forming roll 39. The forming fabric serves to support and carry thenewly-formed wet web downstream in the process as the web is partiallydewatered to a consistency of about 10 dry weight percent. Additionaldewatering of the wet web can be carried out, such as by vacuum suction,while the wet web is supported by the forming fabric.

[0051] The wet web is then transferred from the forming fabric to atransfer fabric 40. In one embodiment, the transfer fabric can betraveling at a slower speed than the forming fabric in order to impartincreased stretch into the web. This is commonly referred to as a “rush”transfer. Preferably the transfer fabric can have a void volume that isequal to or less than that of the forming fabric. The relative speeddifference between the two fabrics can be from 0-60 percent, morespecifically from about 15-45 percent. Transfer is preferably carriedout with the assistance of a vacuum shoe 42 such that the forming fabricand the transfer fabric simultaneously converge and diverge at theleading edge of the vacuum slot.

[0052] The web is then transferred from the transfer fabric to thethroughdrying fabric 44 with the aid of a vacuum transfer roll 46 or avacuum transfer shoe, optionally again using a fixed gap transfer aspreviously described. The throughdrying fabric can be traveling at aboutthe same speed or a different speed relative to the transfer fabric. Ifdesired, the throughdrying fabric can be run at a slower speed tofurther enhance stretch. Transfer can be carried out with vacuumassistance to ensure deformation of the sheet to conform to thethroughdrying fabric, thus yielding desired bulk and appearance ifdesired. Suitable throughdrying fabrics are described in U.S. Pat. No.5,429,686 issued to Kai F. Chiu et al. and U.S. Pat. No. 5,672,248 toWendt, et al. which are incorporated by reference.

[0053] In one embodiment, the throughdrying fabric contains high andlong impression knuckles. For example, the throughdrying fabric can haveabout from about 5 to about 300 impression knuckles per square inchwhich are raised at least about 0.005 inches above the plane of thefabric. During drying, the web can be macroscopically arranged toconform to the surface of the throughdrying fabric and form athree-dimensional surface. Flat surfaces, however, can also be used inthe present invention.

[0054] The level of vacuum used for the web transfers can be from about3 to about 15 inches of mercury (75 to about 380 millimeters ofmercury), preferably about 5 inches (125 millimeters) of mercury. Thevacuum shoe (negative pressure) can be supplemented or replaced by theuse of positive pressure from the opposite side of the web to blow theweb onto the next fabric in addition to or as a replacement for suckingit onto the next fabric with vacuum. Also, a vacuum roll or rolls can beused to replace the vacuum shoe(s).

[0055] While supported by the throughdrying fabric, the web is finaldried to a consistency of about 94 percent or greater by thethroughdryer 48 and thereafter transferred to a carrier fabric 50. Thedried basesheet 52 is transported to the reel 54 using carrier fabric 50and an optional carrier fabric 56. An optional pressurized turning roll58 can be used to facilitate transfer of the web from carrier fabric 50to fabric 56. Suitable carrier fabrics for this purpose are AlbanyInternational 84M or 94M and Asten 959 or 937, all of which arerelatively smooth fabrics having a fine pattern. Although not shown,reel calendering or subsequent off-line calendering can be used toimprove the smoothness and softness of the basesheet.

[0056] In one embodiment, the reel 54 shown in FIG. 2 can run at a speedslower than the fabric 56 in a rush transfer process for building crepeinto the paper web 52. For instance, the relative speed differencebetween the reel and the fabric can be from about 5% to about 25% and,particularly from about 12% to about 14%. Rush transfer at the reel canoccur either alone or in conjunction with a rush transfer processupstream, such as between the forming fabric and the transfer fabric.

[0057] In one embodiment, the paper web 52 is a textured web which hasbeen dried in a three-dimensional state such that the hydrogen bondsjoining fibers were substantially formed while the web was not in aflat, planar state. For instance, the web can be formed while the web ison a highly textured throughdrying fabric or other three-dimensionalsubstrate. Processes for producing uncreped throughdried fabrics are,for instance, disclosed in U.S. Pat. No. 5,672,248 to Wendt, et al.;U.S. Pat. No. 5,656,132 to Farringtonne, et al.; U.S. Pat. No. 6,120,642to Lindsay and Burazin; U.S. Pat. No. 6,096,169 to Hermans, et al.; U.S.Pat. No. No.6,197,154 to Chen, et al.; and U.S. Pat. No. 6,143,135 toHada, et al., all of which are herein incorporated by reference in theirentireties.

[0058] As mentioned above, uncreped through-air dried paper webs madeaccording to the process illustrated in FIG. 2 provide variousadvantages in the process of the present invention. It should beunderstood, however, that other types of paper webs can be used in thepresent invention. For example, in an alternative embodiment, a wetcreped paper web can be utilized.

[0059] For example, referring to FIG. 3, one embodiment of a papermakingmachine is illustrated capable of forming a paper web for use in theprocess of the present invention. As shown, in this embodiment, a headbox 60 emits an aqueous suspension of fibers onto a forming fabric 62which is supported and driven by a plurality of guide rolls 64. A vacuumbox 66 is disposed beneath forming fabric 62 and is adapted to removewater from the fiber furnish to assist in forming a web.

[0060] From forming fabric 62, a formed web 68 is transferred to asecond fabric 70, which may be either a wire or a felt. Fabric 70 issupported for movement around a continuous path by a plurality of guiderolls 72. Also included is a pick up roll 74 designed to facilitatetransfer of web 68 from fabric 62 to fabric 70.

[0061] From fabric 70, web 68, in this embodiment, is transferred to thesurface of a rotatable heated dryer drum 76, such as a Yankee dryer. Web68 is lightly pressed into engagement with the surface of dryer drum 76to which it adheres, due to its moisture content and its preference forthe smoother of the two surfaces. In some cases, however, an adhesivecan be applied over the web surface or drum surface for facilitatingattachment of the web to the drum.

[0062] As web 68 is carried through a portion of the rotational path ofthe dryer surface, heat is imparted to the web causing most of themoisture contained within the web to be evaporated. Web 68 is thenremoved from dryer drum 76 by a creping blade 78. Although optional,creping web 78 as it is formed further reduces internal bonding withinthe web and increases softness.

[0063] Once the paper web is formed, a bonding material is applied toeach side of the web and at least one side of the web is then creped. Ingeneral, for most applications, the paper web will only be creped on oneside after the bonding materials are applied. It should be understood,however, that in some situations it may be desirable to crepe both sidesof the web. Referring to FIG. 4, one embodiment of a system that may beused to apply bonding materials to the paper web and to crepe one sideof the web is illustrated. The embodiment shown in FIG. 4 can be anin-line or off-line process. As shown, paper web 80 made according tothe process illustrated in FIG. 2 or FIG. 3 or according to a similarprocess, is passed through a first bonding agent application stationgenerally 82. Station 82 includes a nip formed by a smooth rubber pressroll 84 and a patterned rotogravure roll 86. Rotogravure roll 86 is incommunication with a reservoir 88 containing a first bonding material90. Rotogravure roll 86 applies the bonding material 90 to one side ofweb 80 in a preselected pattern.

[0064] Web 80 is then contacted with a heated roll 92 after passing aroll 94. The heated roll 92 is for partially drying the web. The heatedroll 92 can be heated to a temperature, for instance, up to about 250°F. and particularly from about 180° F. to about 220° F. In general, theweb can be heated to a temperature sufficient to dry the web andevaporate any water.

[0065] It should be understood, that the besides the heated roll 92, anysuitable heating device can be used to dry the web. For example, in analternative embodiment, the web can be placed in communication with aninfra-red heater in order to dry the web. Besides using a heated roll oran infra-red heater, other heating devices can include, for instance,any suitable convective oven or microwave oven.

[0066] From the heated roll 92, the web 80 can be advanced by pull rolls96 to a second bonding material application station generally 98.Station 98 includes a transfer roll 100 in contact with a rotogravureroll 102, which is in communication with a reservoir 104 containing asecond bonding material 106. Similar to station 82, second bondingmaterial 106 is applied to the opposite side of web 80 in a preselectedpattern. Once the second bonding material is applied, web 80 is adheredto a creping roll 108 by a press roll 110. Web 80 is carried on thesurface of the creping drum 108 for a distance and then removedtherefrom by the action of a creping blade 112. The creping blade 112performs a controlled pattern creping operation on the second side ofthe paper web.

[0067] In accordance with the present invention, the second bondingmaterial 106 is selected such that the web 80 can be creped from thecreping drum 108 while the creping drum is at a relatively lowtemperature. For example, in accordance with the present invention, thecreping drum 108 can be maintained at a temperature of less than 200°F., and particularly less than 150° F. In one embodiment, for example,the creping drum 108 can be at ambient temperatures.

[0068] Since creping is accomplished at relatively low temperatures, thecreping drum 108 can have various constructions. For example, in oneembodiment, the creping drum can be a Yankee dryer that is not heated oronly heated to a relatively low temperature. Alternatively, however, thecreping drum can be a roll having a cast iron surface. The diameter ofthe creping drum can vary and is generally not critical.

[0069] Once creped, paper web 80, in this embodiment, is pulled througha drying station 114. Drying station 114 can include any form of aheating unit, such as an oven energized by infrared heat, microwaveenergy, hot air or the like. Drying station 114 may be necessary in someapplications to dry the web and/or cure the first and second bondingmaterials. Depending upon the bonding agents selected, however, in otherapplications drying station 114 may not be needed.

[0070] The amount that the paper web is heated within the drying station114 can depend upon the particular bonding materials used, the amount ofbonding materials applied to the web, and the type of web used. In someapplications, for instance, the paper web can be heated using a gasstream such as air at a temperature of about 510° F. in order to curethe bonding materials. When using low cure temperature bondingmaterials, on the other hand, the gas can be at a temperature lower thanabout 270° F. and particularly lower than about 250° F. In analternative embodiment, the drying station 114 is not used to cure thebonding material applied to the web. Instead, the drying station 114 isused to dry the web and to drive off any water present in the web. Inthis embodiment, the web can be heated to temperatures sufficient toevaporate water, such as to a temperature of from about 200° F. to about250° F.

[0071] Once passed through drying station 114, web 80 can be wound intoa roll of material 116.

[0072] In one embodiment of the present invention, a low temperaturecure bonding material can be used that is believed to further cure overtime. For example, it has been discovered by the present inventor thatwhen using some types of bonding materials, the wet strength of thetreated paper web increases over time. The increase in wet strength canbe permanent or temporary. For example, increases in wet strength havebeen found to occur over 1 day intervals and 3 day intervals.

[0073] More specifically, particular bonding materials can be chosenthat when applied to a web in accordance with the present invention, thewet strength of the paper product can increase by at least 25% in thecross machine direction 72 hours after application when the paperproduct is stored at ambient temperatures. More particularly, the wetstrength of the web can increase by at least 30%, and more particularlycan increase by at least 35% over a 72 hour period. Further, theseincreases in wet strength can occur in shorter intervals of time, suchas after 48 hours or after 24 hours.

[0074] The bonding materials applied to each side of the paper web areselected for not only assisting in creping the web but also for addingdry strength, wet strength, stretchability, and tear resistance to thepaper. Particular bonding materials that may be used in the presentinvention include latex compositions, such as acrylates, vinyl acetates,vinyl chlorides and methacrylates. Some water-soluble bonding materialsmay also be used including polyacrylamides, polyvinyl alcohols andcellulose derivatives such as carboxymethyl cellulose. In oneembodiment, the bonding materials used in the process of the presentinvention comprise an ethylene vinyl acetate copolymer. In particular,the ethylene vinyl acetate copolymer can be cross-linked with N-methylacrylamide groups using an acid catalyst. Suitable acid catalystsinclude ammonium chloride, citric acid and maleic acid.

[0075] As described above, and in accordance with the present invention,the second bonding material applied to the paper web is a bondingmaterial that can adhere to a creping surface at a relatively lowtemperature. Examples of such bonding materials are produced by AirProducts Corporation. One particular bonding material, for instance, isAIRFLEX EN1165.

[0076] In another embodiment, the low temperature bonding material canbe a bonding material as described in U.S. Pat. No. 6,117,492 toGoldstein, et al., which is incorporated herein by reference. In the'492 patent, a polymeric binder is disclosed that has been reacted witha polyaldehyde. The polyaldehyde can be a dialdehyde such as glyoxal orglutaraldehyde. The polymeric binder can also be reacted with apolyaziridine functional compound.

[0077] The polymeric binder itself can be formed from a variety ofethylenically unsaturated monomers. For example, the polymeric bindercan be formed by combining a vinyl acetate, a (meth)acrylic acid, anacetoacetoxyethyl (meth)ethacrylate, and a C1 to C8 alkyl (meth)acrylicester. Such a polymer can have a glass transition temperature of fromabout −5° C. to about 10° C.

[0078] In general, the first bonding material and the second bondingmaterial can be different bonding materials or the same bondingmaterial.

[0079] The bonding materials are applied to the base web as describedabove in a preselected pattern. In one embodiment, for instance, thebonding materials can be applied to the web in a reticular pattern, suchthat the pattern is interconnected forming a net-like design on thesurface.

[0080] In an alternative embodiment, however, the bonding materials areapplied to the web in a pattern that represents a succession of discreteshapes. Applying the bonding material in discrete shapes, such as dots,provides sufficient strength to the web without covering a substantialportion of the surface area of the web.

[0081] According to the present invention, the bonding materials areapplied to each side of the paper web so as to cover from about 15% toabout 75% of the surface area of the web. More particularly, in mostapplications, the bonding material will cover from about 20% to about60% of the surface area of each side of the web. The total amount ofbonding material applied to each side of the web can be in the range offrom about 4% to about 10% by weight, based upon the total weight of theweb.

[0082] At the above amounts, the bonding materials can penetrate thepaper web from about 10% to about 70% of the total thickness of the web.In most applications, the bonding materials should at least penetratefrom about 10% to about 15% of the thickness of the web.

[0083] Referring to FIG. 5, one embodiment of a pattern that can be usedfor applying a bonding material to a paper web in accordance with thepresent invention is shown. As illustrated, the pattern shown in FIG. 5represents a succession of discrete dots 120. In one embodiment, forinstance, the dots can be spaced so that there are approximately fromabout 25 to about 35 dots per inch in the machine direction or thecross-machine direction. The dots can have a diameter, for example, offrom about 0.01 inches to about 0.03 inches. In one particularembodiment, the dots can have a diameter of about 0.02 inches and can bepresent in the pattern so that approximately 28 dots per inch extend ineither the machine direction or the cross-machine direction. In thisembodiment, the dots can cover from about 20% to about 30% of thesurface area of one side of the paper web and, more particularly, cancover about 25% of the surface area of the web.

[0084] Besides dots, various other discrete shapes can also be used. Forexample, as shown in FIG. 7, a pattern is illustrated in which thepattern is made up of discrete shapes that are each comprised of threeelongated hexagons. In one embodiment, the hexagons can be about 0.02inches long and can have a width of about 0.006 inches. Approximately 35to 40 hexagons per inch can be spaced in the machine direction and thecross-machine direction. When using hexagons as shown in FIG. 7, thepattern can cover from about 40% to about 60% of the surface area of oneside of the web, and more particularly can cover about 50% of thesurface area of the web.

[0085] Referring to FIG. 6, another embodiment of a pattern for applyinga bonding material to a paper web is shown. In this embodiment, thepattern is a reticulated grid. More specifically, the reticulatedpattern is in the shape of diamonds. When used, a reticulated patternmay provide more strength to the web in comparison to patterns that aremade up on a succession of discrete shapes.

[0086] In one particular embodiment of the present invention, a firstbonding material is applied to a paper web according to the patternshown in FIG. 5. A second bonding material, on the other hand, isapplied to a second side of the paper web according to the patternillustrated in FIG. 7. The second bonding material is applied to agreater amount of the surface area than the first bonding material. Forexample, the first bonding material can be applied according to thepattern shown in FIG. 5 and can cover approximately 25% of the surfacearea of the first side of the web. The second bonding material, however,is applied according to the pattern shown in FIG. 7 and coversapproximately 50% of the surface area of the second side of the web.Through this process, a paper product is formed having enhanced overallproperties.

[0087] The process that is used to apply the bonding materials to thepaper web in accordance with the present invention can vary. Forexample, various printing methods can be used to print the latex bondingmaterials onto the base sheet depending upon the particular application.Such printing methods can include direct gravure printing using twoseparate gravures for each side, offset gravure printing using duplexprinting (both sides printed simultaneously) or station-to-stationprinting (consecutive printing of each side in one pass). In anotherembodiment, a combination of offset and direct gravure printing can beused. In still another embodiment, flexographic printing using eitherduplex or station-to-station printing can also be utilized to apply thebonding materials.

[0088] According to the process of the current invention, numerous anddifferent paper products can be formed. In general, the paper productsare single-ply wiper products. The products can be, for instance, facialtissues, bath tissues, paper towels, napkins, industrial wipers, and thelike. As stated above, the basis weight can range anywhere from about 15gsm to about 110 gsm. In one particular embodiment, the presentinvention is directed to the production of a paper towel product havinga basis weight of from about 35 gsm to about 70 gsm.

[0089] The present invention may be better understood with reference tothe following examples.

EXAMPLE 1

[0090] To illustrate the properties of a wiping product made inaccordance with the present invention, an uncreped through-air dried(UCTAD) base web was treated with a bonding material according to theteachings of the present invention and the web was then subjected tovarious standardized tests. The UCTAD base web was formed in a processsimilar to the method shown in FIG. 2. In this particular example, thebase web was made from a stratified fiber furnish containing a centerlayer of fibers positioned between two outer layers of fibers. Bothouter layers of the UCTAD base web contained 100% northern softwoodKraft pulp and up to 6 kg/MT of TQ1003 debonder obtained from theHercules Corporation. The center layer contained 50% softwood Kraft pulpand 50% BCTMP pulp and up to 6 kg/MT of TQ1003 debonder.

[0091] The first side of the web was printed with a bonding materialusing direct rotogravure printing. Then, the printed web passed over aheated roll to evaporate water. Next, the second side of the web wasprinted with the bonding material using a second rotogravure printer.The web was then pressed against and doctored off a rotating drum, whichhad a surface temperature of 125 degrees Fahrenheit. Finally, the sheetwas dried and the bonding material cured and wound into a roll.

[0092] The bonding material in this particular example included AirFlexEN1165, which was obtained from Air Products, Inc. of Allentown, Pa. AirFlex EN1165 contains an ethylene vinyl acetate copolymer.

[0093] The bonding material containing, AirFlex EN1165, had thefollowing formulation: TABLE 1 EN1165 (52% solids, nominal) 10500 gNalco 94PA093 Defoamer 54 g (100% solids) Water 3000 g Catalyst(Ammonium Chloride) 545 g (10% solids) Thickener (Hercules) (2% solids)1100 g Natrasol 250MR

[0094] The samples were then subjected to standardized tests for wet anddry tensile strength and stretch. The term “elongation” refers to theincrease in length of a sample during testing. The tensile strength andthe percent stretch of samples were determined in the machine direction(MD) and in the cross machine direction (CD). The results are expressedin pounds or grams to break and percent stretch before breakage. Highernumbers indicate a stronger, more stretchable fabric.

[0095] During these test, strength was determined using a geometric meantensile strength test (GMT). The size of the samples tested were 3inches in width. During the test, each end of a sample was placed in anopposing clamp. The clamps held the material in the same plane, usuallyvertically, separated by 4 inches and moved apart at a ten inch perminute rate of extension. The clamps moved apart until breakage occurredin order to measure the tensile strength of the sample. The geometricmean tensile strength was then calculated by taking the square root ofthe machine-direction tensile strength of the sample multiplied by thecross-direction tensile strength of the sample.

[0096] Tensile strength tests and elongation tests were performed on aSYNERGY tester available from MTS Systems, Corp. located in EdenPrairie, Minn. Results are reported in grams or in grams per inch widthof sample.

[0097] Wet tensile strength was measured in the same manner as drystrength except that the sample was wetted prior to testing.Specifically, in order to wet the sample, a 3″×5″ tray is filled withdistilled or deionized water at a temperature of 23±2° C. The water isadded to the tray to an approximate 1 centimeter depth.

[0098] A 3M “Scotch-Brite” general purpose scrubbing pad is then cut todimensions of 2.5″ long×4″ wide. A piece of masking tape approximately5″ long is placed along one of the 4″ edges of the pad. The masking tapeis used to hold the scrubbing pad.

[0099] The scrubbing pad is then placed into the water with the tapedend facing up. The pad remains in the water at all times until testingis completed. The sample to be tested is placed on blotter paper thatconforms TAPPI T205. The scrubbing pad is removed from the water bathand taped lightly three times on a screen associated with the wettingpan. The scrubbing pad is then gently placed on the sample parallel tothe width of the sample in the approximate center. The scrubbing pad isheld in place for approximately 1 second. The sample is then immediatelyput into the tensile tester and tested.

[0100] To calculate the wet/dry tensile strength ratio, the wet tensilestrength value was divided by the dry tensile strength value.

[0101] All samples were tested in both the machine direction and thecross direction to obtain percent stretch value.

[0102] To calculate the percent elongation, the length of the sample atrest was divided by the maximum length of the sample prior to breakage.All samples were tested in both the machine direction and the crossdirection.

[0103] The results of the tests obtained when the AirFlex EN1165 bondingagent was used are shown below: TABLE 2 GMT (grams/76 mm) 1387 MDTensile (grams/76 mm) 1602 MD Stretch (%) 26.2 CD Tensile (grams/76 mm)1201 CD Stretch (%) 14.5 CD Wet Tensile 0879.4 CD Wet/Dry Ratio 70.9%

EXAMPLE 2

[0104] In this example, a wiping product was formed as described inExample 1 using a bonding agent, namely AirFlex 426, obtained from AirProducts, Inc. of Allentown, Pa. Air Flex 426 is a polyvinyl acetateemulsion. The bonding material had the following formulation: TABLE 3AirFlex 426 (63% solids, nominal) 8000 g Nalco 94PA093 Defoamer (100%solids)  50 g Water 3920 g Experimental Additive 16055-94A 1250 g (AirProducts) Thickener (Hercules) (2% solids) 1050 g Natrasol 250MR

[0105] Standardized tests for stretch and wet/dry tensile strength wereconducted, as described in Example 1, on a UCTAD base web printed withAirFlex A426 bonding agent in accordance to the present invention. Thefollowing results were obtained: TABLE 4 GMT (grams/76 mm) 1355 MDTensile (grams/76 mm) 1628 MD Stretch (%) 29.2 GD Tensile (grams/76 mm)1128 CD Stretch (%) 11.5 CD Wet Tensile 700.7 CD Wet/Dry Ratio 62.1%

[0106] In this example, the CD wet/dry ratio was tested soon after theproduct was formed and then retested 3 weeks later. Initially, the paperweb was found to have a wet/dry ratio of approximately 30%. The wet/dryratio then increased to approximately 62% over a 3 week time period.Although unknown, it is believed that the bonding material continued tocure over the 3 week storage period.

[0107] These and other modifications and variations to the presentinvention may be practiced by those of ordinary skill in the art,without departing from the spirit and scope of the present invention,which is more particularly set forth in the appended claims. Inaddition, it should be understood that aspects of the variousembodiments may be interchanged both in whole or in part. Furthermore,those of ordinary skill in the art will appreciate that the foregoingdescription is by way of example only, and is not intended to limit theinvention so further described in such appended claims.

What is claimed is:
 1. A method for producing a paper product comprisingthe steps of: providing a paper web comprising softwood fibers, saidpaper web having a first side and a second side; applying a firstbonding material to said first side of said web in a preselectedpattern; applying a second bonding material to said second side of saidweb in a preselected pattern and adhering said second side of said webto a creping surface, said creping surface being at a temperature ofgreater than about 50° F. and less than about 150° F.; and creping saidsecond side of said web from said creping surface.
 2. A method asdefined in claim 1, wherein the paper web further comprises high-yieldfibers.
 3. A method as defined in claim 1, wherein the paper webincludes a middle layer comprising softwood fibers, a first outer layercomprising softwood fibers and a second outer layer also comprisingsoftwood fibers.
 4. A method as defined in claim 2, wherein the paperweb contains high-yield fibers in an amount from about 2% to about 40%by weight.
 5. A method as defined in claim 1, wherein the crepingsurface is at a temperature of less than about 125° F.
 6. A method asdefined in claim 1, wherein the creping surface is at ambienttemperature.
 7. A method as defined in claim 1, wherein the paper webthat is provided comprises an uncreped through-air dried web.
 8. Amethod as defined in claim 1, wherein said paper web further comprises adebonding agent, said debonding agent being added to said web in anamount from about 1 kg/metric tonne to about 6 kg/metric tonne based onthe total weight of fibers contained in said web, said debonding agentinhibiting the fibers in said web from bonding together during formationof said paper web.
 9. A method as defined in claim 1, wherein said firstbonding material is applied to said first side of said paper web in apattern that covers from about 20% to about 40% of the surface area ofsaid first side, and wherein said second bonding material is applied tosaid second side of said paper web in a pattern that covers from about40% to about 60% of the surface area of said second side.
 10. A methodas defined in claim 9, wherein said first bonding material and saidsecond bonding material are applied to said first and second sides ofsaid paper web in a combined amount of from about 4% to about 10% byweight of said paper web.
 11. A method as defined in claim 9, whereinsaid second bonding material is applied to said paper web in apreselected pattern that comprises a succession of discrete shapes. 12.A single ply paper product made according to the process defined inclaim 1, wherein said paper product has a basis weight of from about 15gsm to about 110 gsm.
 13. A method as defined in claim 1, wherein thefirst bonding material and the second bonding material are selected suchthat the wet strength of the paper product increases by at least 25% inthe cross machine direction 72 hours after application of the bondingmaterials when the paper product is stored at ambient temperatures. 14.A method as defined in claim 7, wherein the uncreped through-air driedweb has undergone rush transfer between a first web conveying device anda second web conveying device prior to applying said bonding materials,said web conveying devices having a speed differential of from about 5%to about 45%.
 15. A method as defined in claim 1, wherein the secondbonding material has a glass transition temperature of less than about10° C.
 16. A method as defined in claim 1, wherein the paper web isheated after said first bonding material is applied and prior toapplying said second bonding material, the web being heated to atemperature of at least 150° F.
 17. A method for producing a paperproduct comprising the steps of: providing a paper web comprisingsoftwood fibers, the paper web having a first side and a second side,the paper web comprising an uncreped through-air dried web; applying afirst bonding material to the first side of the web in a preselectedpattern without creping the web; applying a second bonding material tothe second side of the web in a preselected pattern and adhering thesecond side of the web to a creping surface, the creping surface beingat a temperature of less than about 200° F.; and creping the second sideof the web from the creping surface.
 18. A method as defined in claim17, wherein the paper web comprises a stratified paper web having amiddle layer containing softwood fibers, a first outer layer comprisingsoftwood fibers and a second outer layer comprising softwood fibers. 19.A method as defined in claim 17, wherein the paper web containshigh-yield fibers in a amount from about 2% to about 40% by weight. 20.A method as defined in claim 17, wherein the creping surface is at atemperature of less than about 125° F.
 21. A method as defined in claim17, wherein the uncreped through-air dried web has undergone rushtransfer between a first web conveying device and a second web conveyingdevice, said second web conveying device being downstream from saidfirst web conveying device, said second web conveying device moving fromabout 5% to about 45% slower than said first web conveying device.
 22. Amethod as defined in claim 17, wherein the first bonding material andthe second bonding material are applied to the paper web in patternsthat comprise a succession of discrete shapes.
 23. A method as definedin claim 17, wherein the second bonding material is applied in a patternthat covers a greater surface area on the paper web than the patternused to apply the first bonding material.
 24. A method as defined inclaim 22, wherein the second bonding material is applied in a patternthat covers a greater surface area on the paper web than the patternused to apply the first bonding material.
 25. A method as defined inclaim 17, wherein the first bonding material and the second bondingmaterial are selected such that the wet strength of the paper productincreases by at least 25% in the cross machine direction 72 hours afterapplication of the bonding materials when the paper product is stored atambient temperatures.
 26. A paper product comprising: a paper web havinga first side and a second side, the paper web comprising softwoodfibers; a first bonding material applied to the first side of the paperweb in a first preselected pattern; a second bonding material applied tothe second side of the paper web according to a second preselectedpattern, the second side of the paper web being creped according to thesecond preselected pattern; and wherein the first bonding material andthe second bonding material are selected such that the wet strength ofthe paper product increases by at least 25% in the cross machinedirection 72 hours after application of the bonding materials when thepaper product is stored at ambient temperatures.
 27. A paper product asdefined in claim 26, wherein the paper web comprises a stratified paperweb having a first outer layer, a middle layer, and a second outerlayer, the middle layer comprising hardwood fibers or high-yield fibers.28. A paper product as defined in claim 26, wherein the first side ofthe paper web is uncreped.
 29. A paper product as defined in claim 26,wherein the paper product comprises a single-ply wiping product.
 30. Thepaper product as defined in claim 26, wherein the paper web has a basisweight of from about 15 gsm to about 110 gsm.
 31. The paper product asdefined in claim 26, wherein the paper web has a basis weight of fromabout 35 gsm to about 70 gsm.
 32. A paper product as defined in claim26, wherein the first bonding material and the second bonding materialare added to the paper web in a total amount of from about 2% to about20% by weight of the web.
 33. A paper product as defined in claim 26,wherein the second side of the paper web is creped from a crepingsurface at a temperature of less than about 200° F.
 34. A paper productas defined in claim 26, wherein the second bonding material is appliedto the paper web according to a preselected pattern that covers at leastabout 50% of the surface area of the second side of the paper web.
 35. Apaper product as defined in claim 34, wherein the first bonding materialis applied to the web in a preselected pattern that covers less surfacearea than the pattern used to apply the second bonding material.
 36. Apaper product as defined in claim 34, wherein the second bondingmaterial is applied to the paper web according to a pattern thatcomprises a succession of discrete shapes.
 37. A paper product asdefined in claim 34, wherein the first bonding material and the secondbonding material are applied in patterns that both comprise successionsof discrete shapes.
 38. A paper product as defined in claim 26, whereinthe paper web comprises an uncreped through-air-dried web.
 39. A paperproduct as defined in claim 26, wherein the second side of the paper webis creped from a creping surface at a temperature of less than about125° F.